Rub rail renew

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Maerin

Guru
Joined
Jun 30, 2013
Messages
889
Location
USA
Vessel Name
M/V Maerin (Sold)
Vessel Make
Solo 4303
Haulout is coming up in a month. At 20 yrs old, re-bedding is on the list for portlights and rub rail. The lower rubrail is due, I've had some random screws that were loose, some rusting. Plan is to remove the stainless cap, drill & epoxy fill loose screw holes, then re-attach. New screws as needed. I'm debating whether to use butyl tape or 3m 4000 UV caulk on the rail. My concern is that the butyl may have a tendency to squeeze out well after install, creating a cleanup mess that's difficult once back in the water. I believe the butyl will be more resilient when the rubrail... rubs. :)



I'm not sure what I'll use on the portlights, I've not removed any, so I'm not sure what I'll find. But I'm leaning towards butyl on the exterior parts of those. They're manship portlights, they mount from the inside with a flange inside and another loose one that attaches on the outside. The forward ones are subject to sporadic submergence, so a good seal is important!



Recommendations?
 

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Haulout is coming up in a month. At 20 yrs old, re-bedding is on the list for portlights and rub rail. The lower rubrail is due, I've had some random screws that were loose, some rusting. Plan is to remove the stainless cap, drill & epoxy fill loose screw holes, then re-attach. New screws as needed. I'm debating whether to use butyl tape or 3m 4000 UV caulk on the rail. My concern is that the butyl may have a tendency to squeeze out well after install, creating a cleanup mess that's difficult once back in the water. I believe the butyl will be more resilient when the rubrail... rubs. :)



I'm not sure what I'll use on the portlights, I've not removed any, so I'm not sure what I'll find. But I'm leaning towards butyl on the exterior parts of those. They're manship portlights, they mount from the inside with a flange inside and another loose one that attaches on the outside. The forward ones are subject to sporadic submergence, so a good seal is important!



Recommendations?
I will follow this with interest as I am facing the exact same project. I have been assuming I'd use buytl tape to renew the portlight seals.
 
When we redid our rub-rail we started with butyl tape and then went to caulk. The tape was hard to squeeze down and messy. With screws every 6”, I was going back to tighten the screws after a few days in the sun and more tape would squeeze out. I ended up stripping a few screws trying to get the rub rail tight against the hull. With the caulk, it was a quick one shot deal.
 
With butyl you do need to be able to compress it well. Screws may not do it depending on what structure they are going into. As to the ports, I replaced 11 ports last year with New Found Metal ports. I used butyl on them since they are bolted in place. It worked well. I asked the owner of NFM if I could caulk the ports, he said no that they would leak in a few years.
 
Very interesting. Beckson recommends using marine silicone (not hardware store product) for bedding their ports. They recommend against all of the other caulks, and stated that they had not done any long term testing of the butyl tape, so withheld judgement on that product.
 
With butyl you do need to be able to compress it well. Screws may not do it depending on what structure they are going into. As to the ports, I replaced 11 ports last year with New Found Metal ports. I used butyl on them since they are bolted in place. It worked well. I asked the owner of NFM if I could caulk the ports, he said no that they would leak in a few years.

+1 on NFM ports. I had the yard do them, and they used butyl. No leaks after 6 years.

But the NFM flywire screen design is poor. Hard to fit, and the rubber edges of the screens lead to oxygen starvation and surface rust on the exterior SS of the port. The solution would likely be remove the flywire screens, polish and put a couple of coats of wax on the SS before re-fitting the screens. But the screens are such a PITA to fit that the task is low on the list.....
 
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Very interesting. Beckson recommends using marine silicone (not hardware store product) for bedding their ports. They recommend against all of the other caulks, and stated that they had not done any long term testing of the butyl tape, so withheld judgement on that product.

I believe The Beckson recommendation is specific to their plastic framed ports...
I would not extrapolate that to mean it is the recommended sealant for ALL ports... especially SS. Plastic poses very different compatibility challenges for many plastics.

CMS has a very good How To on installing ports w/ Butyl
CMS Marine How To Installing NFM SS Ports

I have used CMS Butyl Tape on a hatch bedding job and was very pleased w/ results and I will add it is very different (and better) than butyl tape I purchased locally from a camper supply. No affiliation other than a satisfied CMS customer
 
I agree on the screens, not easy to install them. The problem with using silicone caulk is that once you use it if you have to recaulk nothing wants to stick to it. The butyl install of the ports is not easy either. It takes much more time than caulk but should last forever. It took me about 1.5 hours per port to pack the butyl in around the port. And that was after I figured out how to do it.
 
These are stainless, the Beckson portlights as others pointed out, plastic, so there's no correlation to what I'm doing. There's no way I'll use silicone caulk, no worries there!



Thanks for the link to CMS' site, I've been there before but didn't review the NFM related info. These Manship portlights AFAIK are very similar. I will look in any event. THX!!
 
Good catch on the fact that Beckson ports are plastic and that the application recommendation of using silicone is specific to that! I knew that, but it slipped my mind (an old guy moment I guess) at the time of posting.

I do not use silicone for anything on the boat, but when the manufacturer gives specific instructions on installation, well, I usually follow that. I have a porthole to install this season and will probably use silicone as recommended, but I do have concerns.

Agree that CMS is a great site and I have listened to Rod's advice for years.
Good luck on your projects,
Tom
 
Haulout is coming up in a month. At 20 yrs old, re-bedding is on the list for portlights and rub rail. The lower rubrail is due, I've had some random screws that were loose, some rusting. Plan is to remove the stainless cap, drill & epoxy fill loose screw holes, then re-attach. New screws as needed. I'm debating whether to use butyl tape or 3m 4000 UV caulk on the rail. My concern is that the butyl may have a tendency to squeeze out well after install, creating a cleanup mess that's difficult once back in the water. I believe the butyl will be more resilient when the rubrail... rubs. :)



I'm not sure what I'll use on the portlights, I've not removed any, so I'm not sure what I'll find. But I'm leaning towards butyl on the exterior parts of those. They're manship portlights, they mount from the inside with a flange inside and another loose one that attaches on the outside. The forward ones are subject to sporadic submergence, so a good seal is important!



Recommendations?
Back to the rub rail issue: the screws thru mine angle down slightly. How will you epoxy fill your screw holes?
 
Back to the rub rail issue: the screws thru mine angle down slightly. How will you epoxy fill your screw holes?
The ones that seem to need attention, I'll over drill by about 1/8" or more to get to good material. I'll wet the holes out with straight west system, slow hardener, then fill with thickened epoxy or more likely I'll use 610 tubes for ease of application My wife has a bunch of tiny cytology brushes that will work perfectly for wetting the holes out. There are a lot of holes. l plan not to be too choosy in selecting the ones for re-work. Probably won't take much more effort to do them all. I'll use a centering countersink bit to mark the filled holes. I do plan to use Sikaflex 291 as bedding. The stainless cap is still secure, this is a proactive measure.
 
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